Question

I have script that takes long time to execute. In a result server responds in 503 error. How can I set longer execution time?

In my PHP script I set:

set_time_limit(0);
ignore_user_abort(true);

Answer 1

This question is very similar to PHP Background Processes. So read that; In addition,

First you need to change the time limit in php.ini; you cannot change it in the script itself. Or in .htaccess using php_value

Second, you may be you want to modify how you interact with user more friendly so that the page uses an update; you can explore ajax; http-refresh; multipart pages for different approaches. If you are doing long calculations perhaps you can launch them in the background and update a database, retrieve the results later.